RE: [802.3ae_Serial] Issue with 1500 Power
juergen
Please check your numbers below. Thanks
Ron Miller
-----Original Message-----
From: Rahn, Juergen (Juergen) [mailto:krahn@xxxxxxxxxx]
Sent: Wednesday, June 27, 2001 3:30 AM
To: stds-802-3-hssg-serialpmd@xxxxxxxx
Subject: AW: [802.3ae_Serial] Issue with 1500 Power
Hi,
as discussed in the PMD call I understand there is a mismatch in the values
defined for the 1550 case. The minimum transmitter OMA is -1.39dBm +
penalties. Link attenuation is set to 13 dB , so this would give a
sensitivity requirement of -14,39 dBm OMA ,. however the stressed
sensitivity (In OMA) is defined to be -11.4 dBm.
so there are 10 dB
difference between those two values.
LOOKS MORE LIKE ABUT 3 DB TO ME.
The trade off that has been introduced
(that I do not like, but this is a different discussion) will shift this
complete link power level. When comparing this with powers and sensitivities
as defined in ITU the following appears: ITU defines 2 dB path penalty with
this OMA we would end at a minimum transmitter power average of about - 1
dBm which is in line to ITU. with 109 dB attenuation there is margin in the
ITU numbers, with 11 dB and ITU sensitivity (Which has been confirmed by
measurements) we add up to 0. ( -14 dBm average power sensitivity and 2 dB
penalty gives us the G.691 application). When simply taking this transmitter
power and 13 dB attenuation we end up with 2 dB better sensitivity
requirement as currently experienced by measurements (worst case EOL).
This may start this conversation.
Regards Juergen